PLEASE HELP ME, I WILL BE ETERNALLY GRATEFUL.

A beam of light passes through the air and enters a diamond at an angle of incidence of 40 degrees. Use Snell’s Law to find the angle of refraction of the diamond. (Index of refraction for air is 1.00 and the index of refraction of a diamond is 2.42.) If the beam of light passed through water at the same angle of incidence, would the angle of refraction from the diamond be the same and if not, by how much would it change? (Index of refraction for water is 1.33.)

Question

PLEASE HELP ME, I WILL BE ETERNALLY GRATEFUL. 

A beam of light passes through the air and enters a diamond at an angle of incidence of 40 degrees. Use Snell’s Law to find the angle of refraction of the diamond. (Index of refraction for air is 1.00 and the index of refraction of a diamond is 2.42.) If the beam of light passed through water at the same angle of incidence, would the angle of refraction from the diamond be the same and if not, by how much would it change? (Index of refraction for water is 1.33.)

anonymous · Answer

I don't know what to do at all honestly and I don't know what snell's law is. I really need someone to walk me through this.

anonymous · Answer

@Compassionate @uri @.Sam. assistance? :(